Related Articles

Coughing is a common reason for a visit to the doctor. In doctors’ offices, urgent care centers and emergency rooms, a cough is likely to be diagnosed as acute bronchitis, which is an infection of the major airways leading to your lungs. About 90 percent of the time, acute bronchitis is caused by a viral infection, and coughs due to acute bronchitis last 10 days to 3 weeks, regardless of the treatment given. If your cough lasts longer, other factors may be prolonging your symptoms, or you may have another condition.

Post-Infectious Cough

Coughing is a reflex mechanism designed to clear foreign material and secretions from your airways and lungs. When your airways are inflamed or infected, coughing helps move mucus, dead cells and infectious organisms upward, where they can be swallowed or spit out. Some organisms, such as Mycoplasma or respiratory syncytial virus, generate airway inflammation that persists after the infection has cleared. In these cases, your cough may last for 3 to 8 weeks. With Bordetella pertussis, the bacterium that causes whooping cough, your cough can linger for months, even though the bacteria that triggered your symptoms have been eliminated.

Smoking Prolongs Cough

In addition to irritating your throat and airways, cigarette smoking reduces your lungs’ ability to clear secretions because it damages the cilia in your airways. Cilia are short, hairlike structures projecting from the cells lining your bronchial tubes, and their constant rhythmic beating helps carry mucus and debris out of your lungs. When bronchitis is superimposed on smoking, airway inflammation is magnified, and mucus secretion increases. Because of poor “mucociliary clearance,” these secretions are not readily removed from a smoker’s airways. Consequently, a cough due to bronchitis may persist longer in a smoker than it would in a nonsmoker.

Bronchitis Aggravates Asthma

Asthma, an inflammatory respiratory disease characterized by hypersensitivity and intermittent narrowing of the airways, is a common cause of a persistent cough. Any factor that increases airway sensitivity -- smoke, fumes, dust, pollen or infection -- can stimulate the muscles that constrict your airways, which in turn generates a cough reflex. A bout of acute bronchitis may serve as the trigger for a stubborn cough in people whose asthma was previously well controlled. If you have asthma, your doctor may recommend you change your daily treatment routine when you have bronchitis.

Considerations

Although acute bronchitis can cause a lingering cough, it is not the only cause. Chronic bronchitis, a form of chronic obstructive pulmonary disease, can cause an ongoing cough that never gets better. Gastroesophageal reflux disease, allergies, asthma, post-nasal drainage, emphysema, pulmonary fibrosis, pneumonia and lung cancer can cause persistent coughing. Depending on the underlying cause of a persistent cough, inhaled antiinflammatories or bronchodilators, such as triamcinolone (Azmacort) or albuterol (Proventil, Ventolin); oral cough suppressants, such as dextromethorphan (Robitussin DM, Delsym) or codeine; acid-blocking medications, such as omeprazole (Prilosec) or pantoprazole (Protonix); antibiotics; or antihistamines might be beneficial. If your cough lasts longer than 3 weeks, contact your doctor for recommendations.

About the Author

Stephen Christensen started writing health-related articles in 1976 and his work has appeared in diverse publications including professional journals, “Birds and Blooms” magazine, poetry anthologies and children's books. He received his medical degree from the University of Utah School of Medicine and completed a three-year residency in family medicine at McKay-Dee Hospital Center in Ogden, Utah.